As a conventional general linear guide device, for example, the linear guide device linear guide device shown in FIG. 5 is known.
The linear guide device shown in FIG. 5 is provided with a guide rail 101 which extends in the axial direction and a slider 102 which straddles the guide rail 101 in a manner able to move relatively in the axial direction.
The two side surfaces of the guide rail 101 are formed with rolling element rolling grooves 103 which extend in the axial direction. The slider body 102A of the slider 102 is formed at the inside surfaces of two sleeve parts 104 with rolling element rolling grooves 107 which face the rolling element rolling grooves 103. Further, between each of the two facing rolling element rolling grooves 103 and 107, as one example of the rolling elements, a large number of balls B are rollably loaded. Through rolling of these balls B, the slider 102 can move relatively over the guide rail 101 in the axial direction.
Along with the movement of the slider 102, the balls B interposed between the guide rail 101 and slider 102 roll and move to the end parts of the slider 102. However, to continuously make the slider 102 move in the axial direction, these balls B have to be endlessly circulated.
For this reason, rolling element passages 108 which run through the axial direction are formed in the sleeve parts 104 of the slider body 102A, and the two ends of the slider body 102A are fastened with substantially lateral U-shaped end caps 105 through for example screws 112 or other fastening means. The end caps 105 are formed with direction changing channels 106 bent in a semi-arcuate shape connecting the two rolling element rolling grooves 103 and 107 and the rolling element passages 108, whereby rolling element endless circulation raceways are formed.
Further, at the two ends of the slider 102 in the axial direction are fastened a pair of side seal members 111 fastened together with the end caps 105 via screws 112 etc. The side seal members 111 are provided for suppressing the generation of dust from the linear guide device. The side seals 111 are made to have a substantially lateral U-shape in the same way as the end caps 105, their inside circumferences are made seal surfaces which slide against the guide rail 101, and the seals are formed by steel sheets on which rubber is baked.
Note that, in FIG. 5, reference numeral 110 indicates a tap hole for a screw 112 formed at an end face of the slider body 102A, 113 indicates a greasing nipple, and 114 indicates a bolt hole for fastening the guide rail 101.
On the other hand, as a side seal member used in a linear guide device for vacuum environment use, for example, the linear guide device shown in FIG. 6 is known (see Patent Document 1).
The side seal member 211 shown in FIG. 6 is fastened together with the end cap (not shown) to an end face of the slider body (not shown) through screws 215. This side seal member 211 includes a plurality of first and second plates 212 and 213 of thin sheet shapes alternately stacked and a holding plate 214 to which these first and second plates 212 and 213 are attached. The first and second plates 212 and 213 of the side seal member 211 are formed with openings 212a and 213a which match the outer shape of the guide rail 201 (see FIG. 7). The holding plate 214 is also formed with an opening 214a which matches the outer shape of the guide rail 201.
The openings 212a and 213a of the first and second plates 212 and 213 which form the side seal member 211 are larger in size than the outer shape of the guide rail 101, so a clearance is formed between the side seal member 211 and the guide rail 201. For this reason, the side seal member 211 moves along the guide rail 201 while maintaining a slight clearance from it, i.e., without contacting the guide rail 201. If explaining this clearance, the openings 213a of the second plates 213 are slightly larger in shape than the openings 212a of the first plates 212. As shown in FIG. 7, the clearance β between the second plates 213 and the guide rail 201 is larger than the clearance α between the first plates 212 and the guide rail 201 whereby a relief shape is formed. By making the clearance between the side seal member 211 and the guide rail 201 a relief shape, when lubricating oil evaporates and the gas flows between the side seal member 211 and the guide rail 201, a large resistance is caused compared with the case of forming the clearance by a flat shape and the lubricant inside of the linear guide device can be better kept from vaporizing and leaking to the outside.